Doctest涉及转义字符

Question

有一个函数fix(),作为输出函数的辅助函数,它将字符串写入文本文件.

def fix(line):
    """
    returns the corrected line, with all apostrophes prefixed by an escape character

    >>> fix('DOUG\'S')
    'DOUG\\\'S'

    """
    if '\'' in line:
        return line.replace('\'', '\\\'')
    return line

打开doctests,我收到以下错误:

Failed example:
    fix('DOUG'S')
Exception raised:
    Traceback (most recent call last):
      File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/doctest.py", line 1254, in __run
        compileflags, 1) in test.globs
      File "<doctest convert.fix[0]>", line 1
        fix('DOUG'S')
                  ^

无论我和我使用什么组合,doctest似乎都不想工作,即使函数本身运行完美.怀疑这是doctest在块评论中的结果,但有任何解决此问题的提示.

Answer 1

这是你想要的吗？:

def fix(line):
    r"""
    returns the corrected line, with all apostrophes prefixed by an escape character

    >>> fix("DOUG\'S")
    "DOUG\\'S"
    >>> fix("DOUG'S") == r"DOUG\'S"
    True
    >>> fix("DOUG'S")
    "DOUG\\'S"

    """
    return line.replace("'", r"\'")

import doctest
doctest.testmod()

原始字符串是你的朋友......